I am trying to change multiply an access decimal field by 60 (Converting from hours to minutes). However, the decimal field precision is set to 4. Some of the values are larger than 4 digits so Access is giving an error that says 'The decimal field's precision is too small to accept the numeric you attempted to add'.
Right now I have,
CLng([Table].[HOURS]*60)
The process needs to be automated, preferably without using VBA code. Is there a way to change the precision of the datatype in a query?
If the max. integer value of the field is 9999, and your hour count can exceed 416, you will have to modify the field of the table.
Related
I have created a column with
day_endnav double precision
When I insert a number: 58.320856084100 in database its stored as 58.3208560841 .
The 2 zeros at the end are removed.
Is there any way to say to mariadb to keep what is entered as it is. Not to roundof or removed zeros at the end?
The two zeros were not "removed". DOUBLE has 53 significant bits, which is about 16 significant decimal digits. The display of the number probably decided they were irrelevant. What tool displayed them?
Whether you insert 58.320856084100 or 58.32085608410000000000000, you will get the same value stored into DOUBLE.
Trailing zeros (at least after the decimal point) have no mathematical meaning to FLOAT or DOUBLE. If you have some meaning, then I guess you need to store it as a string, or DECIMAL.
DECIMAL(mm, 12) will store and display 58.320856084100 (if mm >= 14). However, DECIMAL is "fixed-point". That is, DECIMAL(20,12) will always have exactly 12 decimal places, no more, no fewer.
Please state your goal; maybe I have not touched on that point yet.
I've got an issue when inserting double values into an ms-access database.
I've set the field, size, to be Currency type with 7 decimal places.
In my code, I have the following line to add the value to the query
cmd.Parameters.Add("#size", OleDbType.Double).Value = CDbl(txt_size.Text)
When debugging, I can see the value in the #size parameter is 0.000008, which is what I typed into the text box.
Yet, when I view the record in access after the query has run, it shows as 0.0000000, and therefore when viewing the value in the application is shows as 0.0000 as well.
Why is it rounding the value down? Do I need to change something in Access to allow such small numbers?
The currency data type doesn't support values that precise.
See this page for a description of the currency type. It supports 4 decimals.
In formatting, you can of course increase the amount of decimals displayed, but that doesn't increase the size of the field.
If possible, I'd change the field to a double precision float or a decimal field (data type Number, field size Decimal). Both these types support higher precision than currency.
I have schedule job to pull data from our legacy system every month. The data can sometime swell and shrink. This cause havoc for DECIMAL precision.
I just found this job failed because DECIMAL(5,3) was too restrictive. I changed it to DECIMAL(6,3) and life is back on track.
Is there any way to evaluate this shifting data so it doesn't break on the DECIMAL()?
Thanks,
-Allen
Is there any way to evaluate this shifting data so it doesn't break on the DECIMAL()
Find the maximum value your data can have and set the column size appropriately.
Decimal columns have two size factors: scale and precision. Set your precision to as many deimal paces you need (3 in your case), and set the scale based on the largest possible number you can have.
A DECIMAL(5,3) has three digits of precision past the decimal and 5 total digits, so it can store numbers up to 99.999. If your data can be 100 or larger, use a bigger scale.
If your data is scientific in nature (e.g. temperature readings) and you don't care about exact equality, only showing trends, relative value, etc.) then you might use real instead. It takes less space than a DECIMAL(5,3) (4 bytes vs 5), has 7 digits of precision (vs. 5) and a range of -3.4E38 to 3.4E38 (vs -99.999 to 99.999).
DECIMAL is more suited for financial data or other data where exact equality is important (i.e. rounding errors are bad)
Say I have test results values for a lab procedure that come in as 103. What would be the best way to store this in SQL Server? I would think since this is numerical data it would be improper to just store it as string text and then program around calculating the data value from the string.
If you want to use your data in numeric calculations, it is probably best to represent your data using once of SQL servers native numeric data type. Since you show scientific notation, it is likely you will want to use either REAL or FLOAT.
Real is basically 7 decimal digits of precision and float has 15 digits of precision (at least this is how they are normally used). You can actually specify reduced precision for FLOAT, but in practice most people just use REAL in that case. REAL takes 4 bytes of storage, and FLOAT requires 8 bytes.
The other numeric types are for fixed decimal point arithmetic.
Numbers in scientific notation like this have three pieces of information:
The significand
The precision of the significand
The exponent of 10
Presuming we want to keep all this information as exact as possible, it may be best to store these in three non-floating point columns (floating-point values are inexact):
DECIMAL significand
INT precision (# of decimal places)
INT exponent
The downside to the approach of separating these parts out, of course, is that you'll have to put the values back together when doing calculations -- but by doing that you'll know the correct number of significant figures for the result. Storing these three parts will also take up 25 bytes per value (17 for the DECIMAL, and 4 each for the two INTs), which may be a concern if you're storing a very large quantity of values.
Update per explanatory comments:
Given that your goal is to store an exponent from 1-8, you really only need to store the exponent, since you know the mantissa is always 10. Therefore, if your value is always going to be a whole number, you can just use a single INT column; if it will have decimal places, you can use a FLOAT or REAL per Gary Walker, or use a DECIMAL to store a precise decimal to a specified number of places.
If you specify a DECIMAL, you can provide two arguments in the column type; the first is the total number of digits to be stored, while the second is the number of digits to the right of the decimal point. So if your values are going to be accurate to the tenths place, you might create a column of DECIMAL(2,1). SQL Server MSDN documentation: DECIMAL and NUMERIC types
Help says:
By default, the maximum precision
returns 38.
Examples:
SELECT ##MAX_PRECISION
Of course it is. That should mean, you can somehow change it, right? But I can't find an option for it. Is there some hidden crypted registry key or something?
The problem is that not all applications support precision > 24 and treat such values as text O_o But aggregate functions always return max precision if they not forced to something else.
For example, i need only 15 digits in all queries that return decimals, and don't want to manually CAST every SUM/MIN/MAX operator to decimal(10, 5)...
The MAX_PRECISION simply reflects the maximum internal size of your SQL-Server's representation of floating point numbers. Thus you cannot change it. It's like a parameter telling you that you have 4 GB of memory installed. There is no registry hack to change that amount :-)
However you can specify less than this value in the column datatype or, as you pointed out, you can convert the results.